I know where there's a 53cm Gios w/Dura Ace front-rear for about $475 shipped. I'm sure it's dirty, but it's Columbus SLX and DA, not a bad combo.

Other than that, from 27" to 700c roll the dice, chances are about even. 27 or 700 t 650, the house wins every time.

If you really want 650, you may find them in tri bikes, and "upconvert" them to roadies.

Or buy an East Hill bike and get a really long stem and seatpost. Good luck.